Pulmonary deposition of monodisperse aerosols in patients with chronic obstructive pulmonary disease.

In order to improve patient convenience and drug availability for patients with alpha 1-protease inhibitor deficiency, the administration via the inhalation route has been considered. This study investigated if it is possible to obtain high values of peripheral aerosol deposition by using optimized and controlled inhalation conditions. Therefore, peripheral deposition was studied in 10 patients with alpha 1-protease inhibitor deficiency (phenotype PiZ) and moderate to severe chronic obstructive pulmonary disease by measuring the 24-hour Clearance of radiolabeled inert iron oxide particles with diameters of 2 microns, 3 microns, and 4 microns. Patients inhaled a large volume of aerosol (1000 to 2000 cm3), which was normalized to the individual lung function, with a flow rate of 200 cm3/S. Due to this breathing pattern, peripheral deposition was for all particle sizes above 50% of the inhaled aerosol. The highest peripheral deposition (68%) was found for 3-microns particles.